Protective effects of ginsenoside Rg1 on chronic restraint stress induced learning and memory impairments in male mice

• Rg1 reversed the cognitive impairments in CRS treated mice.
• Rg1 inhibited ROS production and neuronal oxidative injury in CRS treated mice.
• Rg1 decreased the expression of NOX2, p47phox and RAC1 in CRS treated mice.

Alzheimer's disease (AD) is one of the major neurological diseases of the elderly. Chronic stress, which can induce atrophy and functional impairments in several key brain areas such as the frontal cortex and hippocampus, plays an important role in the generation and progression of AD. Currently, there are no effective drug treatment options for preventing chronic stress induced learning and memory impairments and neuronal damage. Ginsenoside Rg1 (Rg1) is a steroidal saponin abundantly contained in ginseng. This study explored the neuroprotective effects of Rg1 on chronic restraint stress (CRS) induced learning and memory impairments in a mouse model. Our results showed that Rg1 (5 mg/kg) significantly protected against learning and memory impairments induced by CRS in a Morris water maze. Besides, Rg1 (2, 5 mg/kg) was able to decrease ROS generation and attenuate the neuronal oxidative damage in the frontal cortex and hippocampus CA1 in mice. Additionally, the inhibition of NOX2, p47phox and RAC1 expression is also involved in the action mechanisms of Rg1 in this experimental model. This study provided an experimental basis for the clinical application of Rg1 in chronic stress induced neuronal oxidative damage.